1. Technical Field
The present invention generally relates to touch control technologies and, particularly to a detecting method for a photo-sensor touch panel and a touch-sensitive electronic apparatus using the same.
2. Description of the Related Art
FIG. 1 is a schematic view of illustrating a method for detecting a central position of a touch area sensed by a photo-sensor touch panel, in accordance with the prior art. As illustrated in FIG. 1, the numerical reference 100 represents an image frame obtained by scanning the photo-sensor touch panel (not shown). The image frame 100 is consisted of 256 data points (as labeled by the numerical reference 102) arranged in a matrix of 16 columns and 16 rows.
In the prior art, a distribution area of data points in the image frame 100 each having a brightness lower than a threshold brightness is defined as the touch area, as represented by the shaded area of FIG. 1; a distribution area of data points in the image frame 100 each having a brightness higher than the threshold brightness is defined as a non-touch area, as represented by the white area of FIG. 1. Accordingly, as long as the coordinate values of data points 104, 106, 108 and 110 of the touch area are acquired and a mean value of the coordinate values of the four data points is calculated, a coordinate value of the data point 112 located at the central position of the touch area can be obtained.
However, the above-mentioned method for detecting the central position of the touch area is easily influenced by shadow and light. For example, when the user uses a forefinger to touch the photo-sensor touch panel, a shadow area caused by the hand of the user has an irregular shape, which would result in the defined touch area may also have an irregular shape. Therefore, if the foregoing method for detecting the central position of the touch area is employed, the central position of the real touch area would easily be wrongly determined and thus renders unsatisfactory the accuracy of coordinate positioning of the photo-sensor touch panel.